Reheater for compound engines



(No Model.) 2 sheetssheet 1.

P.' W. DEAN.

RBHEATER PoR ooMPoUND ENGINES.

No. 457,078. Patented Aug. 4, 1891.

I Q l 4 1' 7mm;

f mwls QZop an.

UNITED STATES PATENT OFFICE.

FRANCIS IV. DEAN, CF CAMBRIDGE, MASSACHUSETTS.

REHEATER FOR ooMPoUND ENGINES.

SPECIFICATION forming part of Letters Patent No. 457,078, dated August 4, 1891w i Application led February 4, 1891. Serial No. 330,152. (No model.)

To all whom it may concern:

Be it known that I, FRANCIS YV. DEAN, of Cambridge, in the county of Middlesex and State of Massachusetts, have invented certain new and useful Improvements in Reheaters for Compound Engines, of which the following, taken in connection with the accompanying drawings, is a specification.

My invention relates to reheaters for use in connection with compound engines for the purpose of superheating the exhaust-steam :from the high-pressure cylinder before it enters the low-pressure cylinder; and it consists in certain novel features of construction, arrangement, and combination of parts, which will be readily understood by reference to the description of the drawings, and to the claims hereinafter given, and in which my invention is clearly pointed out.

Figure l of the drawings is a central longitudinal sectionof my improved reheater, and Fig. 2 is a transverse section of the same on lineac :c on Fig. l.

In the drawings, A is the cylinder, of castiron, provided at the center of its length with theinWardly-proj ectin g T-shaped annular rib A and having formed in one side thereof the passage B, communicating with the exhaustpipe B of the high-pressure cylinder and the passage C, through which and the pipe C the steam exhausted from said high-pressure cylinder after having been reheated escapes into the valve-chest of the low-pressure cylinder. The ends of the cylinder A are closed by the heads A2 and Aan d it has screwed into its underside the two drain-pipes a a., one upon each side of the T-shaped rib A', as shown in Fig. l.

D is a cylinder, made, preferably, of copper or steel and having its ends closed steamtight by the heads D and D2, which serve as tube-sheets to support the series of tubes b b set therein in the usual way of setting boilertubes-that is, by expanding their ends. The cylinder D has riveted thereto upon opposite sides thereof the two re-enforcing disks c c', through which and the shellofsaid cylinderare formed threaded holes to receive the threaded ends of the live-steamsupply pipe E and the discharge pipe F, which pass through packing-boxes d and d', respectively, formed in opposite sides ot the cylinder A, as shown. The cylinder D, when completed, is inserted within the cylinder A at the end to which the head "A2 is secured, fitting loosely within the T-shaped ring or partition A, by which and the stands G G, secured within the cylinder near the head A2, it is supportedin aposition substantially concentric with the axis of the cylinder A, as shown.

The construction of the cylinders A and D and the heads A2 and A3 are such that the exhaust-steam from the high-pressure cylinder, entering the cylinder through the pipe B', surrounds the periphery of the cylinder D at the let't of the partition-rib A', fills the space at the left of tube-sheet D', passes through the tubes b l), surrounds the right-hand half of said cylinder D, and then passes through the pipe C to the valve-chest ofthe low-pressure cylinder, and in the meantime the interior of the cylinder D has been filled with live steam from the boiler, which enters through the pipe E, surrounds all the pipes b b, imparting a portion of its heat thereto and to the shell ofthe cylinder D, which is taken up and absorbed by the exhaust-steam in contact with said cylinder and tubes, thereby considerably increasing the efficiency of the low-pressure cylinder. By this construction and arrangement of the several parts of the heater a very effective relleater is produced for increasing the pressure, and consequently the efficiency of the steam eX- hausted from the high-pressure cylinder preparatory to performing further service in the low-pressure cylinder of a compound engine.

The heater can be built at a comparatively small cost, is easily accessible for cleaning, and the inner cylinder can be readily removed from the outer casing by simply removing the head A2 and unscrewing the pipes E and F, if it should be necessary to do so for any purose. p Another advantage is that the inner cylinder is not subject to unequal expansion, because all parts thereof are heated substantially alike.

Vhat I claim as new, and desire toV secure by Letters Patent of the United States, is-

l. A reheater comprising an outer casing provided with a central inwardly-projecting partition-rib, an inlet-passage on one side ot said partition-rib, and a discharge-passage on` the other side of said rib, a second cylinder lIOC having closed ends and a series of longitudinal tubes extending through said closed ends, said second cylinder being supported Within said partition-rib concentric with the axis of the outer casing and with its ends removed from contact with the heads of said outer casing, a pipe extending through said outer shell and communicating with the interior of said second cylinder for the admission of live steam to the interior of said inner cylinder, and a similar pipe for the escape of said steam.

2. The combination of the cylinder A, provided with the annular partition-rib A', the heads A2 and A3, the inlet-passage B, and the discharge-passage C, the cylinder D, having closed ends and provided with the series of ,tubes b b, said cylinder D being inclosed in the cylinder A, with its ends removed from contact with the heads of said cylinder and surrounded by the partitio1r1ibA,the steaminlet pipe E, the discharge-pipe F, and the stands G G, all constructed, arranged, and operating substantially as described.

In testimony whereof I have signed my name to this specification, in the presence of two subscribing Witnesses, on this 31st day of January, A D. 1891.

FRANCIS 7. DEAN.

Witnesses:

N. C. LOMBARD, WALTER E. LOMBARD. 

